resolves #221 - pixelRatio in timeline
resolves #221 - pixelRatio in timeline

ffxsam/wavesurfer.js,katspaugh/wavesurfer.js,katspaugh/wavesurfer.js,ffxsam/wavesurfer.js,ale-grosselle/wavesurfer.js,agamemnus/wavesurfer.js,agamemnus/wavesurfer.js,ale-grosselle/wavesurfer.js